[xx,yy]=ndgrid(linspace(xl(1),xl(2),10),linspace(yl(1),yl(2),10));

zzm=fres.p10*xx+fres.p01*yy+fres.p00;
surf(xx,yy,zzm,'FaceAlpha',0.85,'FaceLighting','gouraud','FaceColor','interp','AmbientStrength',0.5)


surf(xx,yy,zzm,'FaceAlpha',0.85,'FaceLighting','gouraud','FaceColor','interp','AmbientStrength',0.5)

xlim(xl);
ylim(yl);
zlim(zl);
grid;
hold off

light('Position',[-1 0 0],'Style','local');
lightangle(gca,-45,30);

global AZ
global EL
view(AZ,EL);